Multispectral analysis of magnetic resonance images

Magnetic resonance (MR) imaging systems produce spatial distribution estimates of proton density, relaxation time, and flow, in a two dimensional matrix form that is analogous to that of the image data obtained from multispectral imaging satellites. Advanced NASA satellite image processing offers sophisticated multispectral analysis of MR images. Spin echo and inversion recovery pulse sequence images were entered in a digital format compatible with satellite images and accurately registered pixel by pixel. Signatures of each tissue class were automatically determined using both supervised and unsupervised classification. Overall tissue classification was obtained in the form of a theme map. In MR images of the brain, for example, the classes included CSF, gray matter, white matter, subcutaneous fat, muscle, and bone. These methods provide an efficient means of identifying subtle relationships in a multi-image MR study.     

Personnel costs and perceived benefit of telephone care in the management of children with type 1 diabetes

Intensive management of patients with type 1 diabetes improves control and reduces rates of long-term complications. Telephone care as an adjunct to office visits is important in the management of children with type 1 diabetes in pediatric endocrine practices in the USA. The goal of this project was to assess the personnel costs and patients' perceptions of telephone care in a moderately sized pediatric diabetes care center (301 patients with a diagnosis of type 1 diabetes). There were two parts to this study. First, telephone logs were kept by three pediatric endocrine nurses (2.2 full-time equivalents [FTEs]) and three pediatric endocrinologists (2.0 FTEs) for two 1-wk blocks. Computerized databases were used to determine the number of clinic visits in 1998. Second, a survey assessing the frequency, perceived value and consequences of phone contact with the diabetes team was distributed to 40 families at clinic visits. Mean nurse/certified diabetes educator (CDE) time spent on the phone was 12.1 h/wk, with an additional 9.7 h/wk spent preparing and documenting. Physicians spent 6.4 h/wk on the phone, and 6.1 h/wk preparing/supervising/documenting. For our 301 patients with diabetes, the weekly personnel cost for telephone care at our institution was 1367 US dollars or 236 US dollars/patient/yr. Of the families surveyed, 80% reported that they had used the phone to obtain care for their child with diabetes and 55% had paged the doctor on call in the previous 6 months. Seven patients reported that phone contact prevented a total of 13 emergency department (ED) visits and 35 office visits. Using a cost estimate of 550 US dollars per ED visit, and 103 US dollars per office visit, the cost of prevented visits was 232 US dollars/patient/yr in our center. These data indicate that telephone care is effective in reducing the cost of reimbursable care via the ED and office visits, as well as avoiding hospitalization. However, the cost of providing this telephone care is not reimbursable to providers.     

Hormonal and barrier contraception and risk of upper genital tract disease in the PID Evaluation and Clinical Health (PEACH) study

OBJECTIVE: Among women diagnosed with pelvic inflammatory disease, we examined the associations between hormonal or barrier methods of contraception and upper genital tract infection or inflammation. METHODS: Participants were 563 patients from a treatment trial for pelvic inflammatory disease. All had pelvic pain; pelvic organ tenderness; and leukorrhea, mucopurulent cervicitis, or untreated cervicitis. Contraceptive use within the prior 4 weeks was compared among women with baseline upper genital tract gonorrhea or chlamydia, women with endometritis without upper genital tract gonorrhea or chlamydia, and women with neither upper genital tract gonorrhea or chlamydia nor endometritis. RESULTS: Inconsistent condom use was significantly and independently associated with a 2 to 3 times elevated risk for upper genital tract infection. Upper genital tract gonorrhea or chlamydia was not significantly associated with use of oral contraceptives, use of medroxyprogesterone, condoms used consistently, nor other barrier methods. CONCLUSION: No hormonal or barrier contraceptive method was related to a reduction in upper genital tract disease among women with clinical pelvic inflammatory diseases.     

Functional neuroanatomy of different olfactory judgments

Humans routinely make judgments about olfactory stimuli. However, few studies have examined the functional neuroanatomy underlying the cognitive operations involved in such judgments. In order to delineate this functional anatomy, we asked 12 normal subjects to perform different judgments about olfactory stimuli while regional cerebral blood flow (rCBF) was measured with PET. In separate conditions, subjects made judgments about the presence (odor detection), intensity, hedonicity, familiarity, or edibility of different odorants. An auditory task served as a control condition. All five olfactory tasks induced rCBF increases in the right orbitofrontal cortex (OFC), but right OFC activity was highest during familiarity judgments and lowest during the detection task. Left OFC activity increased significantly during hedonic and familiarity judgments, but not during other odor judgments. Left OFC activity was significantly higher during hedonicity judgments than during familiarity or other olfactory judgments. These data demonstrate that aspects of odor processing in the OFC are lateralized depending on the type of olfactory task. They support a model of parallel processing in the left and right OFC in which the relative level of activation depends on whether the judgment involves odor recognition or emotion. Primary visual areas also demonstrated a differential involvement in olfactory processing depending on the type of olfactory task: significant rCBF increases were observed in hedonic and edibility judgments, whereas no significant rCBF increases were found in the other three judgments. These data indicate that judgments of hedonicity and edibility engage circuits involved in visual processing, but detection, intensity, and familiarity judgments do not.